Hi Michael,

Thanks for your question here!

Unfortunately the USAF 1951 resolution target is not a standard Zemax file. However, you can easily find this target elsewhere such as on the internet (1951 USAF resolution test chart - Wikipedia), and Zemax can use any BMP, JPG, PNG, IMA, or BIM files as the input for the Image Simulation tool.

When downloading your image, please make sure to use the correct folder where Zemax is searching for the images for the Image Simulation analysis. You can find this in Project Preferences under Folders:

You may find more information about the Image Simulation tool in the Help system at:
The Analyze Tab (sequential ui mode) > Image Quality Group > Extended Scene Analysis > Image Simulation

Best,

Csilla

Thank you Csilla. All of the bmp images of the USAF target don't have all of the groups that the target typically has so it looks like I will need to create my own in an illustrator. Thought I'd ask before heading down that road though. Thanks for your help!